Re: Part of the web page being MODIFIED !

From: Bryan Wagstaff (bryanw@xmission.com)
Date: 11/26/02

  • Next message: Pierre BETOUIN: "Re: Basic rules for IPTABLES protection"
    Date: Tue, 26 Nov 2002 11:23:51 -0700
    From: Bryan Wagstaff <bryanw@xmission.com>
    To: Frank Cheong <chocobofrank@hotmail.com>
    
    

    Quoting Frank Cheong <chocobofrank@hotmail.com>:

    > I received complains regarding one of the image on my web site has been
    > modified by a PORN picture ! While the image have resumed normal during
    > the second visit.

    You say you have had complaints, but don't state if you have seen it or
    not. Can YOU repeat the problem?

    > Therefore, the image haven't been modified. So I do want to know what is
    > the possibilities in doing this ?
    > (Like HTTP session hijack, proxy poisoning, someone doing man in the
    > middle etc) any other ways to do that ?

    There are many ways of that sort of thing happening, but you need to do
    more research to find it.

    If this is something you can verify and repeat, I would first check your
    local machine.

    Has the machine been compromized? If no, are you sure?

    If using unmodified versions of the http server, do the checksums match
    those of the source? (assuming you are using Apache or some other Free/Open
    server) When posting back to the group, please include the versions of the
    software you are using.

    Does the problem appear on another similarly configured machine?

    > As these activities mostly happens outside my server boundry, I assume I
    > can't do anything with it, how about any outside parties ?

    You say 'mostly happens outside my server boundary'. Please be more
    specific.

    Do those outside your network ALWAYS see the corrupted pages then the
    proper image? Does everyone inside your network see the corrupted pages?
    If only some machines inside your 'server boundary' see the corrupted
    pages, are those machines within a NAT device? For example, are machines
    within a 192.168.1.* seeing the corrupted pages while 192.168.0.* are
    seeing the original?

    > As I know going for SSL maybe one of the alternative to stop this but
    > this will add on extra processing on my website and it will make it slow.
    > So I don't want to go for it, any other way to secure against this ?

    You need to know where the problem is beore you can fix it. Right now I
    would say you have some script kiddie playing with the site, but I wouldn't
    remove other posibilities without more research.

    If you have a corrupted web server, moving to SSL would not solve the
    problem, it would actually make it appear that you are intentionally
    sending the images.

    For the man-in-the-middle attack, you could test that out by changes to
    your network or Internet connections. If you are a small business, your
    ISP would probably help.

    If someone were performing a targeted man-in-the-middle attack, you need to
    have a trusted root CA give you a cert. (If you have a self-signed or
    unsigned cert, then they could easily forge one.) If you don't already
    have one, those can take a little work and money to get.

    Best of luck!

    bryanw@xmission.com

    --
    


    Relevant Pages

    • Re: ConnectComputer Vista to SBS 2003 fails
      ... If you use a public proxy server to browse the Intrernet, ... Default web site is not listening on "All Unassigned" for port 80. ... Run CEICW to re-configure the network and firewall on the SBS server. ... Add the ConnectComputer server's IP address or FQDN to the Local Intranet ...
      (microsoft.public.windows.server.sbs)
    • Re: Theft of WiFi charge in Florida
      ... >> implicitly given permission to connect. ... >> To access the web site you must use their network. ... And how do you think you get to the server? ...
      (comp.sys.mac.comm)
    • Re: SBS2003 Premium DNS Issue
      ... not want a website hosted inside the internal network for security reasons. ... SBS server to the web server and then use FrontPage, ... >>My company has a web site hosted on the outside. ...
      (microsoft.public.windows.server.sbs)
    • Re: Missing FTP link
      ... and that you should change it to My Network Places. ... I tried to load it to the site but got the error msg "cannot connect to ... Protocol) web site through a fire wall/proxy server and the proxy ...
      (microsoft.public.publisher.webdesign)
    • Re: Missing FTP link
      ... and that you should change it to My Network Places. ... I tried to load it to the site but got the error msg "cannot connect to ... Protocol) web site through a fire wall/proxy server and the proxy settings ...
      (microsoft.public.publisher.webdesign)